Low EGR1 expression predicts poor prognosis in clear cell renal cell carcinoma.

Clear cell renal cell carcinoma (ccRCC) is resistant to conventional therapy due to the deletion of the von Hippel-Lindau (VHL) gene, and novel treatment options are urgently needed. Here, using tissue microarray analysis of 445 cancer tissues and 326 adjacent normal renal tissues obtained from patients with ccRCC, we present the early growth response-1 (EGR1) protein levels are significantly decreased in ccRCC cancer tissues. Consistently, the EGR1 mRNA expression also decreased in cancer tissues based on the transcriptomic data for 599 tumor and normal samples from The Cancer Genome Atlas. Moreover, Patients with ccRCC presenting low EGR1 expression are more prone to exhibit metastasis and a poor prognosis than those with high EGR1 expression. By multivariate Cox regression analysis, EGR1 is determined to serve as an independent prognostic factor for patients with ccRCC. Further cellular biochemical function analyses show that EGR1 may inhibit proliferation, invasion and metastasis of ccRCC. These findings will deepen our understanding of EGR1 function and shed light on precise treatment for ccRCC patients.